Following up on what we had discussed during the conf call, I think the
rough consensus was if we should do anything, it should be through the
existing resolution / device-pixel-ratio MQs, and that the different types
of zooms should not all have the same influence on them.
- Pinch zoom on mobile browsers does not affect the geometry of the
viewport, and as they merely act as a magnifying glass, they should not
offer via media queries the ability to trigger layout changes, so no MQ
should change during this kind of zoom. The use case of serving high
resolution images when zoomed in can already be served by image-set() and
friends.
- Zooms that just change the font size have no reason to affect the
resolution/device-pixel-ratio MQs
- The desktop style of zoom which enlarges everything while keeping the
physical size of the window constant changes the geometry of the viewport,
which is reflected in the width and height MQ. This type of zoom should
also change the resolution / device-pixel-ratio.
Do we want to put that in the spec, or do we prefer to leave zooming
undefined as has been historically the case in CSS? I believe that there
is value here in specifying this, even though we may want to be careful in
the phrasing to allow other types of zooming to emerge.
- Florian